1. Field
One or more embodiments relate to an illumination device, and more particularly, to an illumination device that switches a light emission direction.
2. Description of the Related Art
Generally, an illumination device is used for ensuring the ability to see in a dark place or for displaying a visual effect for advertisement or aesthetic purposes. A light source for the illumination device may be an incandescent lamp, a fluorescent lamp, or a halogen lamp. Recently, light-emitting diodes (LEDs) have been used as an illumination device.
LEDs are a kind of light-emitting device that produces light of various colors through changing of a compound semiconductor material, such as GaAs, AlGaAs, GaN, or InGaInP. LEDs have a long lifetime, may be miniaturized and manufactured to have a light weight, and may be driven at a low voltage due to high directionality. Also, LEDs have an excellent monochromatic peak wavelength, an excellent optical efficiency, low power consumption, and are eco-friendly. Therefore, LEDs are widely used in various fields, such as TVs, computers, lighting, and automobiles, and its application fields are gradually expanded.
An illumination device may need a function that the direction of light emitted from a light source is changed to a desired direction after the illumination device is installed. In this case, the light emission direction may be changed by using a direction changing member formed on the same structure on which the illumination device is installed or by changing the direction of a whole structure.